Sega 999-0921 - Manual (Page 54)

12 - 3 ADJUSTMENT METHOD
Monitor adjustments are made at the time of shipment. Therefore,
do not make further adjustments without a justifiable reason.
Adjusting a monitor which contains high tension parts is dangerous
work. Also, an erroneous adjustment can cause deviated synchro-
nization and image fault, resulting in malfunction.
When making adjustments, utilize a resinous Alignment Rod. Ser-
vicing with bare hands or using tools made of conductive material
can cause electric shock.